Questions: Describe the sampling distribution of p̂. Assume the size of the population is 25,000.
n=800, p=0.1
Choose the phrase that best describes the shape of the sampling distribution of p̂ below.
A. Approximately normal because n ≤ 0.05 N and np(1-p) ≥ 10.
B. Not normal because n ≤ 0.05 N and np(1-p) < 10.
C. Not normal because n ≤ 0.05 N and np(1-p) ≥ 10.
D. Approximately normal because n ≤ 0.05 N and np(1-p) < 10.
Transcript text: Describe the sampling distribution of $\hat{p}$. Assume the size of the population is 25,000 .
\[
n=800, p=0.1
\]
Choose the phrase that best describes the shape of the sampling distribution of $\hat{p}$ below.
A. Approximately normal because $\mathrm{n} \leq 0.05 \mathrm{~N}$ and $\mathrm{np}(1-\mathrm{p}) \geq 10$.
B. Not normal because $n \leq 0.05 \mathrm{~N}$ and $n p(1-p)<10$.
C. Not normal because $\mathrm{n} \leq 0.05 \mathrm{~N}$ and $\mathrm{np}(1-\mathrm{p}) \geq 10$.
D. Approximately normal because $\mathrm{n} \leq 0.05 \mathrm{~N}$ and $\mathrm{np}(1-\mathrm{p})<10$.
Solution
Solution Steps
Step 1: Determining the Shape of the Sampling Distribution
To determine if the sampling distribution of \(\hat{p}\) is approximately normal, we check two conditions:
The sample size \(n\) is less than or equal to 5% of the population size \(N\): \(n \leq 0.05N\) is met.
The product \(np(1-p)\) is greater than or equal to 10: \(np(1-p) \geq 10\) is met.
Since both conditions are met, the sampling distribution of \(\hat{p}\) is approximately normal.
Step 2: Calculating the Mean of the Sampling Distribution
The mean of the sampling distribution of \(\hat{p}\), denoted as \(\mu_{\hat{p}}\), is equal to the population proportion \(p\): \(\mu_{\hat{p}} = 0.1\).
Step 3: Calculating the Standard Deviation of the Sampling Distribution
The standard deviation of the sampling distribution of \(\hat{p}\), denoted as \(\sigma_{\hat{p}}\), is calculated using the formula \(\sqrt{\frac{p(1-p)}{n}}\): \(\sigma_{\hat{p}} = 0.01\).
Final Answer:
The sampling distribution of \(\hat{p}\) is approximately normal with a mean of \(\mu_{\hat{p}} = 0.1\) and a standard deviation of \(\sigma_{\hat{p}} = 0.01\).